Novel Compounds

ABSTRACT

The present invention relates to a tris salt of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione of Formula (A): 
     
       
         
         
             
             
         
       
     
     corresponding manufacture processes, pharmaceutical formulations containing and uses of the aforementioned compound in therapy, particularly in treatment of diseases where under-activation of the HM74A receptor contributes to the disease or where activation of the receptor will be beneficial.

RELATED APPLICATIONS

This application is a Continuation of U.S. application Ser. No.14/840,549 filed Aug. 31, 2015, which is a Continuation of U.S.application Ser. No. 13/133,486 filed Jun. 8, 2011 now U.S. Pat. No.9,163,024, which is a 371 of International Application No.PCT/US09/66941 filed Dec. 7, 2009, which claims the benefit of U.S.Provisional Application 61/120,596 filed Dec. 8, 2008.

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a particular novel salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione.

In particular, the present invention relates to atrishydroxymethylaminomethane (tris) salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (i.e., also defined as8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dionetrishydroxymethylaminomethane (i.e. CAS), or8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione2-amino-2-(hydroxymethyl)-1,3-propanediol (i.e. IUPAC)), herein referredto as the compound of Formula (IA), pharmaceutical formulationscomprising said compound, processes for its preparation and usesthereof.

BACKGROUND OF THE INVENTION

PCT International Patent Publication WO2005/077950 (SmithKline BeechamCorporation) discloses therapeutically active xanthine compounds ofFormula (I):

corresponding manufacture processes of said compounds, pharmaceuticalformulations containing said active compounds and the use of thecompounds in therapy, particularly in the treatment of diseases whereunder-activation of the HM74A receptor contributes to the disease orwhere activation of the receptor will be beneficial.

The compound 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (i.e. thefree acid form) is described in Example 12 as Formula (A) in PCTInternational Patent Application Publication No. WO2005/077950:

WO2005/077950 is incorporated by reference in its entirety.

The present invention now identifies a novel tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (“Formula (A)” asidentified above), also known as8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dionetrishydroxymethylaminomethane (i.e. CAS) or8-chloro-8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione-2-amino-2-(hydroxymethyl)-1,3-propanediol(i.e., IUPAC)) (i.e., where the term tris is an abbreviation of theorganic compound known as trishydroxymethylaminomethane, with theformula (HOCH₂)₃CNH₂). The tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (A)) isherein referred to as Formula (IA),

The tris salt (Formula (IA)) is superior to the free acid (Formula (A))as defined above. In particular, the tris salt has been shown to exhibitenhanced physical stability particularly when compared to the free acidform. By the term “enhanced physical stability” it is meant that thetris salt will remain in its original form and will not readily convert(or partially convert) to another form by hydration during essentialmanufacturing processes. In contrast, the free acid has been found toreadily convert to a hydrated form during aqueous based processingsteps, for example during wet granulation.

Additionally, the tris salt has a higher solubility than the free acid,with an increased C_(max) and decreased T_(max), which indicates fasterabsorption.

SUMMARY OF THE INVENTION

In one aspect, the invention relates to a tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione, i.e., also known as8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dionetrishydroxymethylaminomethane (i.e. CAS) or8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione-2-amino-2-(hydroxymethyl)-1,3-propanediol(i.e., IUPAC) (Formula (IA)).

In another aspect, the compound of Formula (IA) is an anhydrate. In thiscontext, the word anhydrate means the absence of water in the crystallattice.

The compound of Formula (IA) may be amorphous or crystalline. In oneaspect, the compound of Formula (IA) is crystalline.

In one aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised by an x-ray powder diffraction (XRPD)pattern comprising the following peaks:

Position d-spacing (±0.2° 2-theta) (Å) 10.1 8.7 10.5 8.4 12.2 7.3 13.06.8 13.5 6.5 17.3 5.1

In another aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised by an XRPD pattern comprising thefollowing peaks:

Position d-spacing (±0.2° 2-theta) (Å) 10.1 8.7 10.5 8.4 12.2 7.3 13.06.8 13.5 6.5 17.3 5.1 17.5 5.1 17.9 5.0 18.3 4.8 19.2 4.6 19.8 4.5 20.24.4 20.6 4.3 20.9 4.2 21.7 4.1 22.1 4.0 23.3 3.8 23.9 3.7 24.6 3.6 26.33.4 27.1 3.3 27.9 3.2 28.2 3.2 28.6 3.1 29.6 3.0

In another aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised by an XRPD pattern that issubstantially as shown in FIG. 2.

In one aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised by a melting endotherm with an onsetmelting temperature of 212±2° C. as determined by Differential Scanningcalorimetry (DSC). Suitably by using an aluminium pan, lightly crimpedwithout sealing and using a heating rate of 10° C. min⁻¹.

In one aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised by the following absorption peaks inan Attenuated total reflection infrared (ATR-IR) spectrum of the solidproduct: 3370, 3041, 2946, 2858, 1680, 1656, 1528, 1266, 1243, 1078,1068, 1049±1 cm-1.

In another aspect, the compound of Formula (IA) as an anhydrate incrystalline form is characterised in that it has an ATR-IR spectrum thatis substantially as shown in FIG. 6.

As discussed and illustrated throughout, the present invention includescertain solid state crystalline forms. Several methods forcharacterizing such forms exist, and the invention should not be limitedby the methods chosen or the instrumentation used in characterizing thecompounds of the present invention. For example, with regard to x-raydiffraction patterns, the diffraction peak intensities in theexperimental patterns can vary, as is known in the art, primarily due topreferred orientation (non-random orientation of the crystals) in theprepared sample. As such, the scope of the present invention must beconsidered in light of the variability of characterization that isappreciated by those skilled in the art.

In one aspect, the present invention relates to pharmaceuticalcompositions comprising the compound of Formula (IA).

In one aspect, the present invention relates to the use of the compoundof Formula (IA) in therapy.

In another aspect, the present invention relates to the compound ofFormula (IA) for use in the treatment of diseases where under-activationof the HM74A receptor contributes to the disease or where activation ofthe receptor will be beneficial, in particular dyslipidaemia,hyperlipoproteinaemia, diabetic dyslipidaemia, mixed dyslipidaemia,heart failure, hypercholesteraemia, cardiovascular disease,atherosclerosis, arteriosclerosis, hypertriglyceridaemia, Type IIdiabetes mellitus, Type I diabetes, insulin resistance, hyperlipidaemia,anorexia nervosa, obesity, coronary artery disease, thrombosis, angina,chronic renal failure, peripheral vascular disease or stroke.

In another aspect, the present invention relates to the use of thecompound of Formula (IA) in the manufacture of a medicament for use inthe treatment of diseases where under-activation of the HM74A receptorcontributes to the disease or where activation of the receptor will bebeneficial, in particular dyslipidaemia, hyperlipoproteinaemia, diabeticdyslipidaemia, mixed dyslipidaemia, heart failure, hypercholesteraemia,cardiovascular disease, atherosclerosis, arteriosclerosis,hypertriglyceridaemia, Type II diabetes mellitus, Type I diabetes,insulin resistance, hyperlipidaemia, anorexia nervosa, obesity, coronaryartery disease, thrombosis, angina, chronic renal failure, peripheralvascular disease or stroke.

In another aspect, the present invention relates to methods of treatingdiseases where under-activation of the HM74A receptor contributes to thedisease or where activation of the receptor will be beneficial, inparticular dyslipidaemia, hyperlipoproteinaemia, diabetic dyslipidaemia,mixed dyslipidaemia, heart failure, hypercholesteraemia, cardiovasculardisease, atherosclerosis, arteriosclerosis, hypertriglyceridaemia, TypeII diabetes mellitus, Type I diabetes, insulin resistance,hyperlipidaemia, anorexia nervosa, obesity, coronary artery disease,thrombosis, angina, chronic renal failure, peripheral vascular diseaseor stroke, comprising administration of a therapeutically effectiveamount of the compound of Formula (IA).

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows an IR Spectrum of the anhydrate form of the tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)).

FIG. 2 shows an X-ray powder diffraction of the anhydrate form of thetris salt of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula(IA)).

FIG. 3 shows an ¹H NMR Spectrum of the anhydrate form of the tris saltof 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)).

FIG. 4 shows an ¹³C NMR Spectrum of the anhydrate form of the tris saltof 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)).

FIG. 5 shows an Electrospray Ionization Spectrum of the anhydrate formof the tris salt of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione(Formula (IA))

FIG. 6 shows an Attenuated total reflection (ATR) Infrared Spectrum ofthe anhydrate form of the tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)).

DETAILED DESCRIPTION OF THE INVENTION

Throughout the present specification and the accompanying claims thewords “comprise” and variations such as “comprises”, “comprising” are tobe interpreted inclusively. That is, these words are intended to conveythe possible inclusion of other elements or integers not specificallyrecited, where the context allows.

As used herein, the term “therapeutically effective amount” means thatamount of a drug or pharmaceutical agent that will elicit the biologicalor medical response of a tissue, system, animal or human that is beingsought, for instance, by a researcher or clinician. Furthermore, theterm “therapeutically effective amount” means any amount which, ascompared to a corresponding subject who has not received such amount,results in improved treatment, healing, prevention, or amelioration of adisease, disorder, or side effect, or a decrease in the rate ofadvancement of a disease or disorder. The term also includes within itsscope amounts effective to enhance normal physiological function.

As used herein, the term “pharmaceutically acceptable” means a compoundwhich is suitable for pharmaceutical use. Solvates of the compound ofFormula (IA) which are suitable for use in medicine are those whereinthe counterion or associated solvent is pharmaceutically acceptable.

As used herein, the terms “treating” or “treatment” means thealleviation of the symptoms and/or retardation of progression of thedisease, and may include the suppression of symptom recurrence in anasymptomatic patient.

Reference to the compound of Formula (IA) encompasses solvates (e.g.hydrates) of the compound.

Those skilled in the art of organic chemistry will appreciate that manyorganic compounds can form complexes with solvents in which they arereacted or from which they are precipitated or crystallized.

Solvates of the compound of Formula (IA) are included within the scopeof the present invention. As used herein, the term “solvate” refers to acomplex of variable stoichiometry formed by a solute (the compound ofFormula (IA)) and a solvent. Such solvents for the purpose of theinvention may not interfere with the biological activity of the solute.Examples of suitable solvents include, but are not limited to, water,methanol, ethanol and acetic acid and the like.

In one aspect, suitable solvent(s) for use in the present inventionis/are pharmaceutically acceptable solvent(s). Examples of suitablepharmaceutically acceptable solvents include, without limitation, water,ethanol and acetic acid and the like. As used herein, the term “hydrate”refers to a complex of variable stoichiometry formed with or in thepresence of water. In one aspect of the present invention, the solventused is water.

Because of its potential use in medicine, in one aspect the tris salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)) will bepharmaceutically acceptable. The invention includes within its scope allpossible stoichiometric and non-stoichiometric forms of the compound ofFormula (IA).

In one aspect, the present invention relates to the tris salt form of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (Formula (IA)), whichmay include solvates or hydrates thereof.

There is provided as a further aspect of the present invention the useof the compound of Formula (IA), in the manufacture of a medicament foruse in the treatment of dyslipidaemia, hyperlipoproteinaemia, diabeticdyslipidaemia, mixed dyslipidaemia, heart failure, hypercholesteraemia,cardiovascular disease, atherosclerosis, arteriosclerosis,hypertriglyceridaemia, Type II diabetes mellitus, Type I diabetes,insulin resistance, hyperlipidaemia, anorexia nervosa and obesity. Assuch, the compounds are also provided for use in the treatment ofcoronary artery disease, thrombosis, angina, chronic renal failure,peripheral vascular disease or stroke.

Additionally, the present invention provides the use of the compound ofFormula (IA), in the manufacture of a medicament for use in thetreatment of inflammatory diseases or conditions of the joint,particularly arthritis (e.g. rheumatoid arthritis, osteoarthritis,prosthetic joint failure), or of the gastrointestinal tract (e.g.ulcerative colitis, Crohn's disease, and other inflammatory bowel andgastrointestinal diseases, gastritis and mucosal inflammation resultingfrom infection, the enteropathy provoked by non-steroidalanti-inflammatory drugs), of the lung (e.g. adult respiratory distresssyndrome, asthma, cystic fibrosis, or chronic obstructive pulmonarydisease), of the heart (e.g. myocarditis), of nervous tissue (e.g.multiple sclerosis), of the pancreas, (e.g. inflammation associated withdiabetes melitus and complications thereof, of the kidney (e.g.glomerulonephritis), of the skin (e.g. dermatitis, psoriasis, eczema,urticaria, burn injury), of the eye (e.g. glaucoma) as well as oftransplanted organs (e.g. rejection) and multi-organ diseases (e.g.systemic lupus erythematosis, sepsis) and inflammatory sequelae of viralor bacterial infections and inflammatory conditions associated withatherosclerosis and following hypoxic or ischaemic insults (with orwithout reperfusion), for example in the brain or in ischaemic heartdisease.

In a further or alternative aspect there is provided a method for thetreatment of a human subject with a condition where under-activation ofthe HM74A receptor contributes to the condition or where activation ofthe receptor will be beneficial, which method comprises administering tosaid human subject an effective amount of the compound of Formula (IA).

More particularly, the present invention provides a method for thetreatment of dyslipidaemia, hyperlipoproteinaemia, diabeticdyslipidaemia, mixed dyslipidaemia, heart failure, hypercholesteraemia,cardiovascular disease, atherosclerosis, arteriosclerosis,hypertriglyceridaemia, Type II diabetes mellitus, Type I diabetes,insulin resistance, hyperlipidaemia, anorexia nervosa or obesity, in ahuman subject in need thereof, which method comprises administering tosaid human subject an therapeutically effective amount of a compound ofFormula (IA).

As such, these compounds may also find favour in methods for thetreatment of coronary artery disease, thrombosis, angina, chronic renalfailure, peripheral vascular disease or stroke, which methods compriseadministering to said human subject an therapeutically effective amountof the compound of Formula (IA).

The amount of the compound of Formula (IA) which is required to achievethe desired biological effect will, of course, depend on a number offactors, for example, the mode of administration and the preciseclinical condition of the recipient. In general, the daily dose will bein the range of 1 mg to 500 mg, typically 5 mg to 250 mg or 5 mg to 200mg. For example, 7.35 mg, 36.75 mg, 73.5 mg or 147 mg (equiv to 5 mg, 25mg, 50 mg and 100 mg of free acid). An intravenous dose may, forexample, be in the range of 0.01 mg to 0.1 g, typically 0.01 mg to 10mg, which may conveniently be administered as an infusion of from 0.1 μgto 1 mg, per minute. Infusion fluids suitable for this purpose maycontain, for example, from 0.01 μg to 0.1 mg, per millilitre. Unit dosesmay contain, for example, from 0.01 μg to 1 g of tris salt. Thusampoules for injection may contain, for example, from 0.01 μg to 0.1 gand orally administrable unit dose formulations, such as tablets orcapsules, may contain, for example, from 0.1 mg to 1 g. No toxicologicaleffects are indicated/expected when a compound of the invention isadministered in the above mentioned dosage range.

Pharmaceutical Compositions

While it is possible that, for use in the methods of the invention, thecompound of formula (IA) may be administered as the bulk substance, itis preferable to present the active ingredient in a pharmaceuticalformulation, for example, wherein the agent is in admixture with atleast one pharmaceutically acceptable carrier selected with regard tothe intended route of administration and standard pharmaceuticalpractice.

The invention therefore provides a pharmaceutical composition comprisingthe compound of Formula (IA), in association with one or morepharmaceutically acceptable carrier(s), diluents(s) and/or excipient(s).The carrier, diluent and/or excipient must be “acceptable” in the senseof being compatible with the other ingredients of the composition andnot deleterious to the recipient thereof

Accordingly, the present invention provides a pharmaceutical compositioncomprising a) the compound of Formula (IA) and b) one or morepharmaceutically acceptable carriers.

The term “carrier” refers to a diluent, excipient, and/or vehicle withwhich an active compound is administered. The pharmaceuticalcompositions of the invention may contain combinations of more than onecarrier. Such pharmaceutical carriers can be sterile liquids, such aswater, saline solutions, aqueous dextrose solutions, aqueous glycerolsolutions, and oils, including those of petroleum, animal, vegetable orsynthetic origin, such as peanut oil, soybean oil, mineral oil, sesameoil and the like. Water or aqueous solution saline solutions and aqueousdextrose and glycerol solutions are preferably employed as carriers,particularly for injectable solutions. Suitable pharmaceutical carriersare described in “Remington's Pharmaceutical Sciences” by E. W. Martin,18th Edition. The choice of pharmaceutical carrier can be selected withregard to the intended route of administration and standardpharmaceutical practice. The pharmaceutical compositions may compriseas, in addition to, the carrier any suitable binder(s), lubricant(s),suspending agent(s), coating agent(s), and/or solubilizing agent(s).

The formulations include those suitable for oral, rectal, topical,buccal (e.g. sub-lingual) and parenteral (e.g. subcutaneous,intramuscular, intradermal or intravenous) administration. The mostpreferred form of administration is oral.

Formulations suitable for oral administration may be presented indiscrete units, such as capsules, cachets, lozenges or tablets, eachcontaining a predetermined amount of the compound of Formula (IA); as apowder or granules; as a solution or a suspension in an aqueous ornon-aqueous liquid; or as an oil-in-water or water-in-oil emulsion. Ingeneral, the formulations are prepared by uniformly and intimatelyadmixing the active compound of Formula (IA) with a liquid or finelydivided solid carrier, or both, and then, if necessary, shaping theproduct. For example, a tablet may be prepared by compressing ormoulding a powder or granules of the compound of Formula (IA) optionallywith one or more accessory ingredients. Compressed tablets may beprepared by compressing, in a suitable machine, the compound in afree-flowing form, such as a powder or granules optionally mixed with abinder, lubricant, inert diluent and/or surface active/dispersingagent(s). Moulded tablets may be made by moulding, in a suitablemachine, the powdered compound moistened with an inert liquid diluent.

Tablets and capsules for oral administration may contain conventionalexcipients such as binding agents, for example syrup, acacia, gelatin,sorbitol, tragacanth, mucilage of starch or polyvinyl pyrrolidone;fillers, for example, lactose, microcrystalline cellulose, sugar,maize-starch, calcium phosphate or sorbitol; lubricants, for example,magnesium stearate, stearic acid, talc, polyethylene glycol or silica;disintegrants, for example, potato starch, croscarmellose sodium orsodium starch glycollate; or wetting agents such as sodium laurylsulphate. The tablets may be coated according to methods well known inthe art. Oral liquid preparations may be in the form of, for example,aqueous or oily suspensions, solutions, emulsions, syrups or elixirs, ormay be presented as a dry product for constitution with water or othersuitable vehicle before use. Such liquid preparations may containconventional additives such as suspending agents, for example, sorbitolsyrup, methyl cellulose, glucose/sugar syrup, gelatin, hydroxymethylcellulose, carboxymethyl cellulose, aluminium stearate gel orhydrogenated edible fats; emulsifying agents, for example, lecithin,sorbitan mono-oleate or acacia; non-aqueous vehicles (which may includeedible oils), for example almond oil, fractionated coconut oil, oilyesters, propylene glycol or ethyl alcohol; or preservatives, forexample, methyl or propyl p-hydroxybenzoates or sorbic acid. Thepreparations may also contain buffer salts, flavouring, colouring and/orsweetening agents (e.g. mannitol) as appropriate.

Formulations suitable for buccal (sub-lingual) administration includelozenges comprising the compound of Formula (IA) in a flavoured base,usually sucrose and acacia or tragacanth, and pastilles comprising thecompound of Formula (IA) in an inert base such as gelatin and glycerinor sucrose and acacia.

Formulations of the present invention suitable for parenteraladministration conveniently comprise sterile aqueous preparations of thecompound of Formula (IA) the formulation may be isotonic with the bloodof the intended recipient. These preparations could be administeredintravenously, although administration may also be effected by means ofsubcutaneous, intramuscular, or intradermal injection. Such preparationsmay conveniently be prepared by admixing the compound of Formula (IA)with water and rendering the resulting solution sterile and isotonicwith the blood. Injectable compositions according to the invention willgenerally contain from 0.1 to 5% w/w of the compound of Formula (IA).

Thus, formulations of the present invention suitable for parenteraladministration comprising a compound according to the invention may beformulated for parenteral administration by bolus injection orcontinuous infusion and may be presented in unit dose form, for instanceas ampoules, vials, small volume infusions or pre-filled syringes, or inmulti-dose containers with an added preservative. The compositions maytake such forms as solutions, suspensions, or emulsions in aqueous ornon-aqueous vehicles, and may contain formulatory agents such asanti-oxidants, buffers, antimicrobial agents and/or toxicity adjustingagents. Alternatively, the active ingredient may be in powder form forconstitution with a suitable vehicle, e.g. sterile, pyrogen-free water,before use. The dry solid presentation may be prepared by filling asterile powder aseptically into individual sterile containers or byfilling a sterile solution aseptically into each container andfreeze-drying.

Formulations suitable for rectal administration may be presented asunit-dose suppositories. These may be prepared by admixing the compoundof Formula (IA) with one or more conventional solid carriers, forexample, cocoa butter or glycerides and then shaping the resultingmixture.

Formulations suitable for topical application to the skin may take theform of an ointment, cream, lotion, paste, gel, spray, aerosol, or oil.Carriers which may be used include vaseline, lanolin, polyethyleneglycols, alcohols, and combinations of two or more thereof. The compoundof Formula (IA) is generally present at a concentration of from 0.1 to15% w/w of the composition, for example, from 0.5 to 2%.

By topical administration as used herein, we include administration byinsufflation and inhalation. Examples of various types of preparationfor topical administration include ointments, creams, lotions, powders,pessaries, sprays, aerosols, capsules or cartridges for use in aninhaler or insufflator or drops (e.g. eye or nose drops).

Ointments and creams may, for example, be formulated with an aqueous oroily base with the addition of suitable thickening and/or gelling agentsand/or solvents. Such bases may thus, for example, include water and/oran oil such as liquid paraffin or a vegetable oil such as arachis oil orcastor oil or a solvent such as a polyethylene glycol. Thickening agentswhich may be used include soft paraffin, aluminium stearate, cetostearylalcohol, polyethylene glycols, microcrystalline wax and beeswax.

Lotions may be formulated with an aqueous or oily base and will ingeneral also contain one or more emulsifying agents, stabilising agents,dispersing agents, suspending agents or thickening agents.

Powders for external application may be formed with the aid of anysuitable powder base, for example, talc, lactose or starch. Drops may beformulated with an aqueous or non-aqueous base also comprising one ormore dispersing agents, solubilising agents or suspending agents.

Spray compositions may be formulated, for example, as aqueous solutionsor suspensions or as aerosols delivered from pressurised packs, with theuse of a suitable propellant, e.g. dichlorodifluoromethane,trichlorofluoromethane, dichlorotetrafluoroethane,1,1,1,2,3,3,3-heptafluoropropane, 1,1,1,2-tetrafluoroethane, carbondioxide or other suitable gas.

Capsules and cartridges for use in an inhaler or insufflator, of forexample gelatin, may be formulated containing a powder mix of a compoundof the invention and a suitable powder base such as lactose or starch.

The pharmaceutical compositions according to the invention may also beused in combination with other therapeutically active agents, forexample in combination with other classes of dyslipidaemic drugs (e.g.statins, fibrates, bile-acid binding resins or nicotinic acid).

The compound of Formula (IA) may be used in combination with one or moreother therapeutically active agents for example in combination withother classes of dyslipidaemic drugs e.g.3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) orfibrates or bile acid binding resins or nicotinic acid.

In one aspect, the present invention provides a combination comprisinga) a compound of Formula (IA) and b) one or more therapeutically activeagents.

The invention thus provides, in a further aspect, the use of such acombination in the treatment of diseases where under-activation of theHM74A receptor contributes to the disease or where activation of thereceptor will be beneficial and the use of the compound of formula (IA)in the manufacture of a medicament for the combination therapy ofdyslipidaemia, hyperlipoproteinaemia, diabetic dyslipidaemia, mixeddyslipidaemia, heart failure, hypercholesteraemia, cardiovasculardisease, atherosclerosis, arteriosclerosis, and hypertriglyceridaemia,Type II diabetes mellitus, Type I diabetes, insulin resistance,hyperlipidaemia, anorexia nervosa or obesity.

When the compounds of the present invention are used in combination withother therapeutic agents, the compounds may be administered eithersequentially or simultaneously by any convenient route.

The combinations referred to above may conveniently be presented for usein the form of a pharmaceutical formulation and thus pharmaceuticalformulations comprising a combination as defined above optimallytogether with a pharmaceutically acceptable carrier or excipientcomprise a further aspect of the invention. The individual components ofsuch combinations may be administered either sequentially orsimultaneously in separate or combined pharmaceutical formulations.

When combined in the same formulation it will be appreciated that thetwo components must be stable and compatible with each other and theother components of the formulation and may be formulated foradministration. When formulated separately they may be provided in anyconvenient formulation, conveniently in such a manner as are known forsuch compounds in the art.

When in combination with a second therapeutic agent active against thesame disease, the dose of each component may differ from that when thecompound is used alone. Appropriate doses will be readily appreciated bythose skilled in the art.

The invention thus provides, in a further aspect, a combinationcomprising the compound of Formula (IA) together with anothertherapeutically active agent. An example of another therapeuticallyactive agent being Niacin or Atorvastatin sodium.

The combination referred to above may conveniently be presented for usein the form of a pharmaceutical formulation and thus pharmaceuticalformulations comprising a combination as defined above together with apharmaceutically acceptable carrier thereof represent a further aspectof the invention.

The compounds of the present invention have a useful duration of action.

Methods of Preparation

The present invention further provides a process for preparing the trissalt of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione as shown inScheme 1 below.

Stages 1, 2 3, 4 and 5 are as described in WO2005/077950, which isincorporated by reference by its entirety.

Stage 1: Alkylation of guanosine with allyl bromide

Stage 2: Diazotisation with sodium nitrite followed by hydrolysis toform the xanthine

Stage 3: Chlorination

Stage 4: Alkylation at N3 and/or dialkylation at Ni and N3

Stage 5: Palladium catalysed removal of the allyl group

Alternatively, stage 5 may also be carried out by deprotection withdimethylbarbituric acid.

The final stage in the preparation of the tris salt is combining acompound of formula (A) with trishydroxymethylaminomethane as shownbelow:

The Examples set forth below are illustrative of the present inventionand are not intended to limit in any way, the scope of the presentinvention.

EXAMPLES Example 1 Preparation of8-Chloro-3-Pentyl-3,7-Dihydro-1H-Purine-2,6-Dione Tris Hydroxyl MethylAminomethane Salt (i.e., Also Known As8-Chloro-3-Pentyl-3,7-Dihydro-1H-Purine-2,6-Dione-2-Amino-2-(Hydroxymethyl)-1,3-Propanediol(I.E., IUPAC)

A slurry was formed of 1.0 gram of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione in 10 volumes ofacetonitrile to which 1.1 equivalents of tris(hydroxymethyl)aminomethanewas added in 1.2 volumes of water. The reaction mixture was heated toreflux at approx. 75 to 77° C., which dissolved the aforementionedcomponents. Initial dissolution of components was followed by rapidspontaneous crystal formation. Crystals of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione tris hydroxyl methylaminomethane salt were isolated by filtration (Product Yield: 94%).

Example 2 Preparation of8-Chloro-3-Pentyl-3,7-Dihydro-1H-Purine-2,6-Dione Tris Hydroxyl MethylAminomethane Salt

A slurry was formed of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione(22 kg, contains approximately 16% water) and acetone (125 L) to which asolution of tris(hydroxymethyl)aminomethane (9.3 kg) in water (79.8 kg)was added at room temperature. After heating to near reflux temperatureto approximately 55° C., the solution was filtered through a 1.2 micronfilter cartridge at 55° C. and the batch temperature was adjusted to 61to 63° C. After holding for 30 min, the solution was cooled to 53 to 57°C. and seeded with seed crystals (0.062 kg), which were made in the sameway from an acetone water crystallisation or, as obtained such as, orfrom a procedure of Example 1 above, as a slurry in acetone (2 L). Inthe process, the crystallisation is seeded in order to provide controlof particle size and to ensure the desired product form was obtained.

The mixture was stirred at 53 to 57° C. for 1 hour. The resulting slurrywas then slowly cooled with stirring to 18 to 22° C. and acetone (75 L)was charged over 30 minutes. After stirring at 18 to 22° C. for 30minutes, the resulting slurry was cooled to −5 to 0° C., held for 18hours, filtered, and washed with pre-cooled (−5 to 0° C.) acetone (754The resulting 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione trishydroxyl methyl aminomethane salt was dried at 45 to 50° C. undervacuum. Yield: 18.2 kg (67% yield).

Example 3 Preparation of8-Chloro-3-Pentyl-3,7-Dihydro-1H-Purine-2,6-Dione Tris Hydroxyl MethylAminomethane Salt

8-Chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione (29 kg) was dissolvedin DMSO (40 L) at an elevated temperature of approx. 90 to 100° C. andfiltered through a 5 micron filter, followed by a DMSO (13 L) line wash.Tris(hydroxymethyl)aminomethane (15.1 kg) was dissolved in water (44 L)and filtered through a 5 micron filter into the same vessel as theparent acid, followed by a water (15 L) line wash. The contents of thevessel were then heated to approximately 95° C. to ensure a clearsolution was obtained. Contents were cooled to 88° C. and seeded withseed crystals, where the seed crystals, made in same way from an acetonewater crystallisation or, as obtained such as, or from a procedure ofExample 1 above. In this process, the crystallisation is seeded in orderto provide control of particle size and to ensure the desired productform was obtained. The seeded slurry was held for approximately 30minutes and cooled to 0° C. The product was isolated by filtration,washed with ˜5° C. DMSO/water (1:1, 58 L) and ˜5° C. acetone (2×584 Theresulting product was dried at 50° C. under vacuum. Yield: 35.4 kg (83%yield)

Example 4 Preparation of8-Chloro-3-Pentyl-3,7-Dihydro-1H-Purine-2,6-Dione Tris Hydroxyl MethylAminomethane Salt Formulation

Quantity (mg/tablet) Component 25 mg 50 mg 100 mg Granulation Tris salt¹36.75 73.50 147.00 Mannitol Powder 9.25 18.50 37.00 Povidone 2.50 5.0010.00 Crospovidone 1.50 3.00 6.00 Purified Water² q.s. q.s. q.s.Compression Blend Microcrystalline Cellulose 338.00 280.00 172.00Crospovidone 8.00 16.00 24.00 Magnesium Stearate³ 4.00 4.00 4.00 AqueousFilm Coating Opadry White OY-S-9603 12.00 12.00 12.00 Purified Water²q.s. q.s. q.s. Tablet Weight 412.00 412.00 412.00 ¹An amount of 36.75mg, 73.50 mg or 147.00 mg of Tris salt is required to achieve the 25 mg,50 mg or 100 mg free acid respectively, calculated by a conversionfactor of 1.47. The amount of drug substance may be adjusted based onthe purity assay. ²Water is removed during processing. ³Vegetablesource.

The tris salt, mannitol powder, povidone, crospovidone and purifiedwater were granulated by utilising a fluid bed granulator. The fluid bedwas then dried. The granulation was then blended with microcrystallinecellulose, crospovidone and magnesium stearate and compressed on atablet press. The resulting tablets were then covered in an aqueous filmcoating of opadry and water.

Povidone (polyvinylpyrrolidone) is a synthetic polymer consisting oflinear 1-vinyl-2-pyrrolidone groups and mean molecular weights rangingfrom about 10,000 to about 700,000 supplied by BASF Chemicals. Povidoneis used as a binder during the granulation process.

Crospovidone is a crosslinked povidone, and is a water-insoluble tabletdisintegrant and dissolution agent used at 2 to 5% concentration intablets. It is supplied by BASF Chemicals.

Opadry White OY-S-9603 is a proprietary film-coating material suppliedby Colorcon. Reference is made to the Colorcon Drug Master File Number721 for the manufacturing and control of Opadry White OY-S-9603 AqueousFilm Coating.

According to the instant invention, the various forms of compounds ofthe present invention (i.e. which include solvates thereof) aredistinguished from each other using different characterization oridentification techniques. Such techniques, include solid state ¹³CNuclear Magnetic Resonance (NMR), ³¹P Nuclear Magnetic Resonance (NMR),Infrared (IR), Raman, X-ray powder diffraction, etc. and/or othertechniques, such as Differential Scanning calorimetry (DSC) (i.e., whichmeasures the amount of energy (heat) absorbed or released by a sample asit is heated, cooled or held at constant temperature).

Specifically, the tris salt of the present invention is substantially asshown by the data described in FIGS. 1 to 6.

The following characterizing data were generated for thetrishydroxymethyl amino methane (tris) salt of8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione of the presentinvention (Formula (IA)).

It will be recognised that spectra and diffraction data will varyslightly according to various factors such as the temperature,concentration and instrumentation used.

Example 5 UV/Visible Absorption Spectrum

The UV/Visible Absorption Spectrum was obtained in acetonitrile:water,95:5. A 0.02 mg/ml sample of the tris salt was prepared and analysedwith a 1 cm path length. Spectra were accumulated at a scan rate of 300nm/min on a Varian Cary 50 spectrometer.

Absorbance maxima (nm), λ_(max) Molar Absorption Coefficient, (ε) 27812500 206 20700

Example 6 Differential Scanning Calorimetry (DSC): Melting Point

The melting point or thermal behaviour of the tris salt of the presentinvention was investigated with differential scanning calorimetry (DSC).The onset of melting is typically observed at 212° C.±2° C.

The DSC trace was obtained using a TA Q1000 calorimeter. The sample wasweighed into an aluminium pan, a pan lid placed on top and lightlycrimped without sealing the pan. The experiment was conducted using aheating rate of 10° C. min⁻¹.

Example 7 and 8: ¹H and ¹³C Nuclear Magnetic Resonance Spectra ¹H NMRspectra were acquired on a 400 MHz Varian spectrometer at 298 K. Samplewas dissolved in DMSO-d₆ and chemical shifts were reported in ppmrelative to the tetramethylsilane (TMS) signal at 0 ppm. Couplingconstants (J) are in units of hertz (Hz). Splitting patterns describeapparent multiplicities and are designated as s (singlet), d (doublet),t (triplet), q (quartet), dd (double doublet), dt (double triplet), m(multiplet), br (broad).

¹H NMR (400 MHz, DMSO-d₆) δ ppm: 10.07-5.41 (br, 7H), 3.80 (t, 2H), 3.52(s, 6H), 1.61 (m, 2H), 1.29 (m, 1H), 1.28 (m, 2H), 0.86 (t, 3H)

¹³C NMR spectra were acquired on a 100 MHz Varian spectrometer at 298 K.Sample was dissolved in DMSO-d₆ and chemical shifts were reportedrelative to the TMS signal at 0 ppm.

¹³C NMR (100 MHz, DMSO-d₆, 25 mg/mL 25° C.) δ ppm: 157.0, 151.0, 150.9,142.8, 115.2, 61.0, 59.4, 42.0, 28.4, 27.3, 22.0, 13.9

Example 9 Positive Ion Electrospray Ionization Mass Spectrum

Mass spectra were collected on a Q-TOF Premier LC-MS. Samples weredissolved in acetonitrile/water and ionized by electrospray ionization.The desolvation gas temperature was at 350° C. and the desolvation gasflow rate was 600 L/hr. The spray voltage was 3.5 kV and the sourcetemperature was maintained at 120° C. The collision gas flow rate was0.5 ml/min.

The accurate mass of the protonated molecule was measured at 257.0804Da. The calculated mass of this ion is 257.0805 Da.

MS (m/z): 257.0804 Da [M+H]⁺: 187, 170, 144 (measurement accords withelemental composition of this ion with an error of 0.3 ppm)

Example 10 Infrared Spectrum (IR)

ATR Infrared spectrum: Peak Wavenumber (cm⁻¹) 3370, 3041, 2946, 2858,1680, 1656, 1528, 1266, 1243, 1078, 1068, 1049.

The DATR infra red spectrum was acquired after 128 scans at 4 cm-1resolution on a SensIR Travel IR DATR.

Example 11 X-Ray Powder Diffraction (XRPD)

The tris salt of 8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dione ofthe present invention is crystalline as indicated by X-ray powderdiffraction (XRPD) data and is as shown in FIG. 2.

The X-ray powder diffractogram (XRPD) shown in FIG. 2 was obtained on aPANalytical X'Pert Pro powder diffractometer fitted with an X'Celeratordetector and utilising a fixed divergence slit. The acquisitionconditions were: radiation: Cu Kα, generator tension: 40 kV, generatorcurrent 40 mA, start angle: 2.0° 2θ, end angle 40° 2θ, step size 0.017°2θ. The sample was spun during data acquisition. Characteristic XRPDangles and d-spacings are recorded in Table 1.

TABLE 1 Characteristic XRPD peak angles and d-spacings The skilledperson will recognise that XRPD peak positions are affected bydifferences in sample height. The peak positions quoted herein are thussubject to a variation of +/−0.2 degrees 2-theta. Position d-spacing(±0.2° 2-theta) ((Å)) 10.1 8.7 10.5 8.4 12.2 7.3 13.0 6.8 13.5 6.5 17.35.1 17.5 5.1 17.9 5.0 18.3 4.8 19.2 4.6 19.8 4.5 20.2 4.4 20.6 4.3 20.94.2 21.7 4.1 22.1 4.0 23.3 3.8 23.9 3.7 24.6 3.6 26.3 3.4 27.1 3.3 27.93.2 28.2 3.2 28.6 3.1 29.6 3.0

Example 12 Elemental Analysis

The stoichiometry of the tromethamine (tris) salt is confirmed by theelemental analysis data presented, which is in agreement with thetheoretical values for the corresponding molecular formula.

Molecular Formula C₍₁₄₎H₍₂₄₎N₍₅₎S₍₀₎ Element % w/w Theoretical % w/wFound C 44.5 44.7 H 6.4 6.3 N 18.5 18.5

It is to be understood that the invention is not limited to theembodiments illustrated hereinabove and the right is reserved to theillustrated embodiments and all modifications coming within the scope ofthe following claims.

The various references to journals, patents, and other publicationswhich are cited herein comprise the state of the art and areincorporated herein by reference as though fully set forth.

What is claimed is:
 1. A method for treating stroke in a human subjectin need thereof, comprising administering to said subject atherapeutically effective amount of a compound which is crystalline8-chloro-3-pentyl-3,7-dihydro-1H-purine-2,6-dionetris(hydroxymethyl)aminomethane anhydrate (Formula (IA)):

having an XRPD pattern as shown in FIG.
 2. 2. The method according toclaim 1 wherein the crystalline form of the compound is characterised byan XRPD pattern comprising the following peaks: Position d-spacing(±0.2° 2-theta) ((Å)) 10.1 8.7 10.5 8.4 12.2 7.3 13.0 6.8 13.5 6.5 17.35.1 17.5 5.1 17.9 5.0 18.3 4.8 19.2 4.6 19.8 4.5 20.2 4.4 20.6 4.3 20.94.2 21.7 4.1 22.1 4.0 23.3 3.8 23.9 3.7 24.6 3.6 26.3 3.4 27.1 3.3 27.93.2 28.2 3.2 28.6 3.1 29.6 3.0


3. The method according to claim 1 wherein the crystalline form of thecompound is characterised by a melting endotherm with an onset meltingtemperature of 212±2° C. in a DSC thermogram.
 4. The method according toclaim 1 wherein the crystalline form of the compound is characterised bythe following absorption peaks in an ATR-IR spectrum of the solidproduct: 3370, 3041, 2946, 2858, 1680, 1656, 1528, 1266, 1243, 1078,1068, 1049±1 cm-1.
 5. The method according to claim 1 wherein thecrystalline form of the compound is characterised in that it has an ATRinfra red spectrum that is substantially as shown in FIG. 6.